Nano-scaled silver has received much attention due to its unique electrical conductivity, optical properties, and catalytic capabilities, which allows its potentially wide applications in microelectromechanical system (MEMS) designs. There are many methods to synthesize Ag nanoparticles, for instance, electroless metalization, sol-gel method, vapor deposition, thermal decomposition and reduction of metal salts. Most of the studies are focused on the synthesis of thin layers of Ag films, however, the construction of 3-D silver structures through wet chemical reactions is of extreme lack.
Generally, micro-structures and macro-morphologies play an important role in determining the properties of materials. Morphological modification of crystals through controlled formation is therefore necessary toward the micro- and macro-designs. However, current technologies are limited in their control of the shapes of crystals in solutions. Fukuyo and Imai (Morphological evolution of silver crystals produced by reduction with ascorbic acid. J. Crystal Growth, 241, 193-199, 2002, incorporated herein by reference) obtained silver crystals by reduction of AgNO3 with L-ascorbic acid, however, the unusual morphologies of the crystals (flower-like clusters) greatly limit their applications.